Coil Packs & Plugs

[timmyt101]

I'm getting the low-speed, low-RPM jerk/misfire of a bad plug/coil pack on my 2007 Explorer (4.6 3V).

I know my way around a motor pretty well, but the seized/broken plug issues on these Explorers scares the crap out of me. I've read TSB 08-7-6 and it's straight forward about the 1/8-1/4 turn and soaking with carb cleaner, but still bothers me.

Would I be OK replacing the coil packs (a pretty easy job) to see if that takes care of my issue or attempt the plugs at the same time? I have 76,000 easy miles on the vehicle, so not at the 100,000 mile Ford recommendation on plugs, but you never know.

Thanks for your comments/recommendations/experiences.

Tim

 

[DavidEBSmith]

I would try coil packs first simply because it's easy.

If you don't want to spend the money on all of them at once, you could buy one and install it and see if it makes any difference. If not, re-install the one you just took out on the next cylinder, see if that makes a difference, and keep going down the line until you find that removing one solves the problem (or you've gone through all of them and it hasn't solved the problem).

FWIW we just replaced all the plugs for the second time at about 80K on this set (160K overall) and did the transmission filter/change and one of those things cured the jerk/misfire that was starting to come back. Good news was that the plugs that came out were the updated ones that supposedly don't break as easy, and none did.

 

[timmyt101]

Thanks, David.

I really think I'll take the chance on the coil packs first - easy and hopefully the solution. BTW, how did your plugs look @ 80,000 - I'm not that far away!

Tim